Pre-operative CT scans of 546 patients with biopsy-proven primary bronchial carcinoma were reviewed. Twenty-two patients had a solid adrenal tumour (2 bilateral). Sixteen underwent percutaneous fine needle aspiration (FNA). Malignant cells were aspirated in five, eight revealed benign cells and in three cases there was insufficient material for diagnostic purposes. Six patients did not undergo FNA, four of these were considered to have benign adenomas on CT. This was confirmed by the unchanged CT image at more than 21 months follow-up. The five subjects with FNA-proven metastases died at a median of 14 months (range 3-24 months). All five would have been regarded as operable on their staging chest CT scan. Five patients with a negative biopsy underwent surgery, two died of metastases at 6 and 11 months respectively and one died of post-operative complications. The other two have unchanged adrenal lesions on CT at 9 months and 25 months. The CT appearances of these lesions were analysed. Well defined, low attenuation lesions which had a smooth attenuation rim or only involved part of the gland were benign and the survivors had unchanged CT appearances at follow-up (six lesions in five patients). Of these four lesions were less than or equal to 2 cm in diameter. Low attenuation lesions without a rim were malignant (n = 2). These latter both measured more than 2 cm in diameter. The CT appearances of many adrenal lesions were insufficiently distinctive to exclude malignancy and biopsy was necessary to establish a diagnosis.